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1.
Southern blot analysis of DNAs from Chinese hamster x mouse and rat x mouse somatic cell hybrids showed that the mouse gene encoding androgen-binding protein/sex hormone-binding globulin (ABP-SHBG) is on Chromosome 11. Progeny from an intersubspecies backcross were analyzed to position this locus, termed Shbg, between Il-3 and Int-4 in the middle of this chromosome. Shbg is thus closely linked to several neurological mutations, one of which, Tr, is also associated with male sterility. The recent finding that ABP-SHBG is found throughout the rat brain raises the possibility that one of these mutations may be due to a defect in Shbg. 相似文献
2.
Intact plants and isolated leaves of Zostera capricornii Martens ex Aschers were transferred from daylight to darkness. Substantial amounts of chloropyll a and b continued to accumulate in immature and mature tissue in the same ratio as in the light and were incorporated into chlorophyll-protein complexes in the thylakoids. A small amount of protochlorophyllide also accumulated in immature tissue in the dark. Proplastids and immature chloroplasts continued to develop into mature chloroplasts in the dark in the normal manner but prolamellar bodies, which are a conspicuous feature of immature chloroplasts, took longer to disperse than in the light. Protochlorophyllide accumulation and prolamellar-body formation were not correlated. The results indicate that Zostera has a genetic capacity for dark chlorophyll synthesis which is expressed in immature and mature leaf tissue and enables this plant to continue synthesising chlorophyll and assembling chloroplasts at night.Abbreviations Chl
chlorophyll
-
T
o
time of transfer to darkness 相似文献
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Ion and macromolecular transport in the alveolar macrophage 总被引:3,自引:0,他引:3
E D Robin J D Smith A R Tanser J S Adamson J E Millen B Packer 《Biochimica et biophysica acta》1971,241(1):117-128
5.
Martin L. Adamson 《Systematic parasitology》1981,3(4):209-216
Summary
Rhigonema infecta (Leidy, 1849) Christie & Cobb, 1927, a member of the family Rhigonematidae sensu Théodoridès, 1965, is redescribed from the diplopod Narceus annularis from Sharbot Lake and Long Point, Ontario, Canada. R. infecta is most similar to R. subtruncatum Dollfus, 1952 but differs from this species in possessing four rather than three post-cloacal papillae in the male. Rhigonematids have been affiliated with members of the order Oxyurida by most authors but study of R. infecta suggests that rhigonematids should be placed in their own order, the Rhigonematida. Members of the order Rhigonematida are characterized by: two spicules in the male; H-shaped excretory system; are round to oval sperms; thick and smooth egg-shell; apparently lacking a uterine layer; and development in the egg involving no moults and resulting in a long, thin, coiled larva. In contrast, oxyuridans have a single spicule, the excretory system is X-shaped, the sperm is comet-shaped and the egg-shell has a prominent striated uterine layer. Development in the egg involves at least one and probably two moults and results in a short, robust, uncoiled larva. ac]19810310 相似文献
6.
Keith W.T.Goulding 《中国科学:生命科学英文版》2005,48(Z2)
The nitrogen (N) cycle is essentially 'leaky'. The losses of small amounts of nitrate to waters and of ammonia and nitrous oxide to the atmosphere are a part of the global biogeo-chemical N cycle. However, intensive agricultural production, industry and vehicle use have more than doubled the amount of 'reactive' N in the environment, resulting in eutrophication, ecosystem change and health concerns. Research has identified agricultural practices that cause large losses of N and, in some cases, developed solutions. This paper discusses the problems of maintaining productivity while reducing N losses, compares conventional with low input (integrated) and organic farming systems, and discusses wider options. It also looks at the need to integrate studies on N with other environmental impacts, set in the context of the whole farm system, to provide truly sustainable agricultural systems. 相似文献
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Globin synthesis on reticulocyte membrane-bound ribosomes 总被引:1,自引:0,他引:1
W R Woodward S D Adamson H M McQueen J W Larson S M Estvanik P Wilairat E Herbert 《The Journal of biological chemistry》1973,248(5):1556-1561
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